Merck locates frozen batch of undisclosed Ebola vaccine, will donate for testing in Uganda’s outbreak

The pharmaceutical giant has acknowledged to Science that it has up to 100,000 doses of an experimental vaccine in its freezers in Pennsylvania and will donate them. The World Health Organization and the Ugandan government are trying to figure out how to incorporate these doses into one or more clinical trials of other candidate vaccines that could launch as soon as next month.

Sudan ebolaviruses is the pathogen that is currently circulating in Uganda. The product was quietly made in 2015 and 2016 after it had a success with a vaccine against a different virus that caused a large outbreak in West Africa. The vaccine was frozen and never tested on humans. Scientists have high hopes that the Sudan ebola vaccine will be safe and effective because it has been shown to protect monkeys.

Mark Feinberg, who was in charge of the company's program to develop the vaccine, said that the disclosure was good news. The vaccine is able to move forward quicker than would have been possible. Feinberg is the head of the International AIDS Vaccine Initiative, which is working on a vaccine for Sudan ebolaviruses. He told Science he didn't know his employer had made a vaccine.

The new Uganda outbreak has not been brought up in public discussions of how to deal with it, and the company issued confusing messages to Science about it. In an email sent on 13 October, the company acknowledged for the first time that it had made the vaccine, but said that it had expired and would be destroyed in four years. The company said that the vaccine was still in bulk and that it would be donated.

The company will pay for the process of filling and finishing, which will take about a month. Beth-Ann Coller, the head of product development for the company, says they are doing everything they can to move it as fast as possible.

The Uganda Ministry of Health has reported that Sudan ebola has killed 28 people in Uganda. There have been a few cases of the outbreak in the capital city of Uganda, Kampala. Two districts in Uganda have been placed under lock and key.

Public health measures such as isolating patients and quarantining their contacts can bring about an end to an outbreak. Hopes have been raised that Uganda can stop the outbreak quicker. Nicole Lurie is the U.S. director for the Coalition for Epidemic Preparedness Innovations.

The Sudan ebolaviruses is a livestock pathogen that rarely causes harm in humans and is one of the reasons why the vaccine is made. One of three countries ravaged by the West African epidemic, the largest ever recorded, had a trial of a vaccine against the disease. Regulators in the United States and the European Union approved the vaccine.

Chimpancho adenoviruses are used by the University of Oxford and the nonprofit Sabin Vaccine Institute to make vaccines. Both are racing to get enough to go to Uganda. A company that can do the fill and finish is being sought. The Serum Institute of India is partnering with Oxford.

There is another wild card.

Several scientists tell Science that they are confident that all three Sudan Ebola vaccines will protect people to varying degrees, but they think the most promising vaccine is the one that protects against the VSV. The VSV vaccine has been shown to be more robust and durable in monkey studies, as well as the Ervebo version, which has helped stem several outbreak.

The WHO was collaborating with health officials in Uganda to design a protocol to test the Oxford and Sabin candidates with a strategy known as a "ring vaccination." In the trial of the Zaire version, that approach was utilized. An expert group is reviewing the evidence and will advise on which vaccine to test first.

Small market

There is a tortured history of the vaccine for the disease. The Public Health Agency of Canada and the U.S. Army Medical Research Institute of Infectious Diseases collaborated on the development of the platform used in the vaccine. The monkeys were given a single dose of the vaccine and it protected them against the fatal dose of the disease. Smaller animal studies showed that a vaccine against the Sudan ebolaviruses could be effective. In 2016 Science published a survey of 50 leading vaccine researchers who ranked a Sudan ebolaviruses vaccine as the top priority.

Because the market is so small, pharmaceutical companies didn't pay much attention to the vaccine. There wasn't much incentive to invest in the shots for decades because of the small number of cases that happened in Africa. NewLink Genetics didn't do anything with the vaccine that was licensed to them.

In a matter of months, tens of thousands of people were stricken with the disease in West Africa, including a few in the United States and Europe. The vaccine had not performed as well as the two men would have liked. We had vaccines that were developed in the early 2000s, and we knew that they would work, but we were just lab guys.

If control measures didn't improve, scientists at the U.S. Centers for Disease Control and Prevention projected that the two countries could have more than one million cases of the deadly disease by the end of the year. Feinberg says that the vaccine was licensed by the company. He says that Merck knew from the beginning that it wouldn't be profitable. For public health reasons, they were moving it.

By the time public health measures began to put the brakes on West Africa's epidemic, other major vaccinemakers had already developed their own candidates. More than 11,000 people died and nearly 29,000 fell sick. The ring vaccine trial, conducted with WHO and local health officials, crossed the finish line in mid 2015, but other candidates were too late. The vaccine was given away by the company to someone else.

Ervebo is a standard part of the response when there is an outbreak of the disease. More than 300,000 people werevaccinated during the world's second largest Ebola outbreak, which caused more than 3000 reported cases in a conflict-riven area.

The vaccine for Sudan ebolaviruses is not being developed by the company. The license for that vaccine was given back to it's original owner. The U.S. government awarded IAVI a grant worth up to $126 million to use upgraded technology to develop a vaccine for Sudan ebolaviruses and the related filoviruses.

When the Uganda outbreak began in September, he was once again beside himself, because the vaccines are still at an early stage of development. He says that he sent an email to his boss that said, "Look, we are in the same situation as in 2014)" The vaccine that works in ring vaccinations would be perfect to stop this. The data shows that the vaccine provides robust protection in the monkeys.

Conflicting emails

It has become clear that there is a large amount of vaccine available for clinical trials.

Richard Peluso, who ran vaccine bioprocessing for the company after Feinberg left, told his boss that if the vaccine worked, the company had an advantage. The vaccine was made under strict good manufacturing practices by the company.

It's not clear when the company realized those stocks were still around. Science asked the company if they had made the vaccine and kept it. In the year 2015–16, the company made around 70% of its total capacity. The vaccine candidate for Sudan ebolaviruses expired in 2021. The email stated that 96,000 filled vials of the Marburg vaccine had been destroyed by the company.

On October 20th, the company acknowledged that it did retain bulk quantities of the frozen vaccine and arranged an interview with the interviewer. She says that the fill-and- finished doses of the Sudan vaccine were destroyed by the company. She says that when they're stored frozen, they become brittle.

She says that the end of the shelf life of the bulk product was disclosed by the company. Company scientists were surprised that the vaccine was still in the freezer. She said that it hadn't yet been destroyed. We immediately looked at that and thought we could help. The vaccineBulk Marburg vaccine was destroyed

After attending a WHO meeting that ended on 6 October in which she learned Uganda's outbreak was rapidly growing, she started a search to see if the Sudan vaccine still existed. She says that the vaccine was still being tested to see if it was free of contaminants. "We were not sure about whether or not we would be able to use that bulk material and didn't want to speak out of turn until we knew that we could actually do with it"

The Sudan vaccine was never done with humans. There hasn't been an outbreak of this virus since Uganda's last one in 2012. Perhaps it could have been better.